Reverse engineering a Nokia LCD

LCD displays taken from old Nokia phones have been a staple of the hardware makers for years now, so we’re very happy to see [Andy] reverse engineering a full color QVGA display so we can move our grayscale projects over to a full-color display.

The screen in a Nokia 2730, 5000, and 7100 cell phone is a wonder of technology – its 18-bit color with a very high-resolution piqued [Andy]’s interest. He bought a second-hand Nokia 2730 off of eBay and started taking it apart. After checking out the schematics for the phone, [Andy] had a few breakout boards made; especially useful since he found a few connectors as well.

With a great deal of Googling, [Andy] found another lost soul who successfully broke into a similar LCD display and discovered it was command-compatible with a Magnachip LCD controller. The only way forward was to send a few of these commands over to the display and watch what happens.

[Andy] managed get pixels drawn on the screen, and found a few interesting features: hardware scrolling is enabled, as is changing between portrait or landscape orientations. From a second-hand phone on eBay, [Andy] now has a very nice QVGA display. We’re calling this a win, but you can judge the video after the break for yourself.

The problem with these cellphone lcds are the small pitch connector. If you are looking for a easy-er to use lcd with kinda the same size/rezolution there are on ebay lcds with solderable ribbon with manageable pitch for about 6$ (using the ili9325 controller). The quality of these are probably the same as a copy (knock-off?) lcds (maybe better). Search for 240×320.

pitch of trace points is a problem on pretty much all highly-integrated stuff. Most notably BGA chips and LCD->PCB connectors.

I find printing the PCB and reflowing it in an oven is the homebrew hackers best practice for these. The only real task is getting resolution right on the printing, but once done it’s mass production time. Also there are some tricky aspects of PCB making since these are often high-frequency circuits. Big companies usually solve this with the material over traces, but they have to be stenciled and cut..